1. Field of the Invention
The present invention relates generally ink storage and distribution for ink jet printers and, more specifically, to a high capacity ink replenishing system for ink jet printers that the present invention relates to an automatic sensing device for use on bulk material handling devices.
2. Description of the Related Art
Ink jet printers are a type of computer printer that reproduces a digital image by propelling variably-sized droplets of liquid or molten material ink onto a page. These type of computer printers are well known and have become widely used in conjunction with personal computers for both home and much small office use due to their increased performance and decreased cost of initial acquisition. Such printers range from small inexpensive consumer models to very large and expensive professional machines. However, the major disadvantage to such devices is the cost of replacement ink cartridges, which can greatly offset the lower capital acquisition cost quickly and with only moderate use.
In the worldwide consumer market, four manufacturers account for the majority of inkjet printer sales: Canon®, Hewlett-Packard®, Epson®, and Lexmark®. These printers contain a scanning carriage for supporting one or more disposable print cartridges. Each disposable print cartridge contains a supply of ink in an ink reservoir, a printhead, and ink channels which lead from the ink reservoir to ink ejection chambers formed on the printhead. An ink ejection element, such as a heater resistor or a piezoelectric element, is located within each ink ejection chamber. The ink ejection elements are selectively fired, causing a droplet of ink to be ejected through a nozzle overlying each activated ink ejection chamber so as to print a pattern of dots on the medium. When such printing takes place at 300 dots per inch (dpi) or greater, the individual dots are indistinguishable from one another and high quality characters and images are printed.
Once the initial supply of ink in the ink reservoir is depleted, the print cartridge is disposed of and a new print cartridge is inserted in its place. The printhead, however, has a usable life which outlasts the ink supply. Methods have been proposed to refill these single-use-only print cartridges, but such refilling techniques require penetration into the print cartridge body in a manner not intended by the manufacturer and typically require the user to manually inject the ink into the print cartridge. Additionally, the quality of the refill ink is usually lower than the quality of the original ink. As a result, such refilling frequently results in ink drooling from the nozzles, a messy transfer of ink from the refill kit to the print cartridge reservoir, air pockets forming in the ink channels, poor quality printing resulting from the ink being incompatible with the high speed printing system, and an overall reduction in quality of the printed image.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention; however, the following references describe methods or apparatus for supplying ink in a bulk manner to lower the cost of delivery.
U.S. Pat. No. 7,089,973 describes a cartridge refilling system in which a retail facility provides commercial refilling services.
U.S. Pat. No. 6,785,483 describes a method of job scheduling in order to extend the life of an ink sump.
U.S. Pat. No. 6,846,071 describes an ink supply apparatus which provides continuous refilling for large-format inkjet printers.
U.S. Pat. No. 6,666,552 describes a check valve and diaphragm arrangement designed for the removal of air in an attempt to extend the time available for storing a quantity of ink.
U.S. Pat. No. 6,565,197 describes an ink jet printer that incorporates a high volume ink reservoir.
U.S. Pat. No. 5,880,748 describes an ink delivery system having an automatic pressure regulating system.
U.S. Pat. No. 5,704,403 describes a device for refilling a printer cartridge of an ink jet printer.
U.S. Pat. No. 5,631,681 describes a system and method for replenishing the ink in ink reservoirs of the printhead cartridges on an inkjet printer.
U.S. Pat. No. 5,367,328 describes an automatic ink refilling system for otherwise disposable inkjet cartridges.
Consequently, there still exists a need for an ink replenishing system that maintains the benefits of existing conventionally available inkjet printers but lowers the overall operating cost of current conventional designs by increasing the bulk ink distribution capacity, thereby allowing per unit savings through ‘bulk’ pricing.